Cross-wire switch



July 25, 1950 c. N. HlCKMAN CROSS WIRE swITcH 2 Sheets-Sheet 1 Filed April 10, 1948 INVENTOR C. N. H/CKMA/V ATTORND July 25, 1950 c. N. HICKMAN CROSS WIRE swncn 2 Sheets-Sheet 2 Filed April- 10, 1948 @J JQEJQE Patented July 25, 1950 CROS S -WIRE SWITCH Clarence N;

Hickman, Jackson Heights, N. Y.,

assignor tov Bell Telephone Laboratories, Incorporated, New York, York N. Y;, a corporation of New- Application April 10, 1948, Serial No. 20,303

in a second series of planes perpendicular to the line conductors. Each set of line conductors therefore intersects each set of trunk conductors with each line conductor being in close proximity but out of contact with a trunk conductor at the point of intersection. At each point of juncture between the sets of line and trunk conductors, there is provided a rod which carries insulated contacting media for establishing connections between the line and the trunk conductors. Means are provided to selectively operate any of the I'OdS1t0 bring the contacting media into. position.

to bridge the gaps-between the individual line and the trunk conductors at the selected cross-point. These means may comprise ladder-type coordinately positioned select and hold tapes which are suitably apertured to accept the individualcontact rods. The configuration of the apertures in the tapes is such that upon the conjoint operation of a select and a hold tape, the selected contact rod is moved to establish the aforementioned electrical connections.

In order to meet certain circuit requirements, means have also been provided to operate auxiliary contacts upon the operation of each select or hold tape, such means comprising additional contacting media on certain of the contact rods to indicate that a certain select tape has been actuated, and wire spring pile-ups associated with the hold magnet armatures to indicate that a certain hold tape has been actuated.

The features of the invention will hereinafter be discussed in detail with reference to the accompanying drawings in which:

Fig. 1 is an. isometric view of a switch constructed in accordance with the invention with certain portions broken away and with certain duplicate parts omitted for purposes of clarity;

Fig. 2 is an enlarged View of a portion of Fig. 1 showing the interrelationship of the elements at a typical cross-point;

hers I, a top member 2, and a base member 3". A,

plurality of line conductors 4' are arranged in sets: of four in a series of horizontal planes. Each line conductor 4 is affixed to a bracket 5, mounted on one side member I, through a tension spring 6. The bracket 5 may be of insulating material and the line conductors may be further insulated through theuse of insulating discs I- (Fig. 2) between the conductors and the tension springs 6. Atthe other end, each line conductor 4 is aflixed to a terminal I l" which passes through a slot 8 in side member I, through a slot 9 in insulating sheet l6 and is riveted to terminal strip [2, also of insulating material.

A plurality of trunk conductors l3 are arranged in sets of iour'in a series oi'vertical planes. Each trunk conductor l3 is affixed at its lower end to a terminal 14 which passes through a slot I5 in base member 3', through a slot H5 in in sulating sheet H and is riveted to terminal strip ll! of insulating-material. At the upper end, each trunk conductor I3 is connected through a tensioning spring Hi to a terminal 20 which passes through a slot 2 l in top member 2, through aslot 22 in insulating sheet 23 and is riveted to terminal strip 24*. It is evident that no insulating discs 1 will be used'in connection with the trunk conductors [3. Each of the sets of terminals H, HI and 20" are preferably aligned so that they may be easily multipled-if such is required. As may be seen in Figs. land- 2, the sets of line conductors intersect the sets of trunk conductors with the individual line conductors in each set arranged in proximity to but out of contact with the individual trunk" conductors withwhich they are matable.

material. The contact rods 25 are ing against front cover 29, the latter being preferably made of a transparent material mounted in a frame 30 so that the functioning of the apparatus may be observed. Contacting media 3| (Fig. 2) are properly located on each contact rod 25 so that when the contact rod is moved to its operated position, each of the contacting media will bridge the gap between an associated line conductor 4 and trunk conductor l3. These contacting media are preferably of precious metal and may be sprayed on the insulated contact rods, or may be separate tubular elements pressed on the insulated contact rods.

The contact rods 25 are loosely mounted in support plate 21 both so that the rod may be freely pivoted about this point within the requisite limits, and also to permit a rotary motion of the rod as the contacting media are rolled into contact with the trunk conductors as will be hereinafter described. Such rolling movement not only insures good electrical contact but also provides a continuously changing contacting surface which distributes the wear for a longer service life.

Thecontact rods 25 are selectively actuated by means of a plurality of coordinately positioned ladder-type tapes. A series of select tapes 32 are mounted in parallelism one with the other and extend vertically in the depicted embodiment. A select tape 32 is provided for each set of trunk conductors l3 and each such tape comprises a thin strip of metal or other suitable material having an aperture 33 therein for each set of line conductors 4. Each select tape 32 is slid ably supported in a suitably apertured bottom select guide 34 and top select guide 35. At its uppermost end, each of the select tapes 32 is attached by means of a ribbon 36, a threaded connector 31 and a nut 38 to the armature extension 39 of its respective select magnet 40. The select tapes 32 may either be connected to springs at their lower extremes or may be gravity biased to return to their normal unoperated positions.

A series of hold tapes 4| are mounted in parallelism one with the other and extended horizontally in the depicted embodiment. A hold tape 4! is provided for each set of line conductors 4 and each such tape comprises a thin strip having an aperture 42 therein for each set of trunk conductors l3. Each hold tape 4| is slidablysu ported in a suitably apertured left hold guide 43 and right hold guide 44. At its righthand end, each hold tape 4| is attached by means of a ribbon 45, a threaded connector 46 and a nut 41 to armature extension 48 of its respective hold magnet 49. Through each set of registering apertures 33 in select tapes 32 and 42 in hold tapes 4| passes one of the contact rods 25. Since the select tapes are springor gravitybiased to normally remain at the lower extreme of their movement, and since the hold tapes 4| are biased by means of springs 50 to normally remain at the left-hand extreme of their move ment, the contact rods 25 normally rest out of contact with the associated line and trunk conductors as is depicted in Figs. 1 and 2.

The select and hold tapes are operated by means of select magnets 40 and hold magnets 49, respectively, which have been positioned for optimum efiiciency and compactness. In the preferred embodiment, select magnets 44 may be arranged in two rows with the cores of the magnets in the rearmost row extending vertically and the cores in the other row exterfding horizontally. The magnetic circuit of each of the select magnets 40 in the rearmost row is from the core through L-shaped pole-piece 5|, pivoted armature 52 and back to the core. The magnetic circuit of each of the select magnets 40 in the front row isfrom the core through L- shaped pole-piece 53, pivoted armature 54 and back to the core. In both cases, armature extensions 39 are firmly affixed to their respective armatures 52 and 54 and move therewith. The armature extensions 39 extend toward the front of the relay and their frontmost ends, which lie approximately in plane, are bifurcated to accept select-tape threaded connectors 37. The positioning of the select tapes 32 is accomplished through the adjustment of nuts 38. The length of select-tape travel is adjusted by means of studs 55 which bear against pole-piece 53 and also act as armature back stops. Lock nuts 58 may be provided. It may be seen that upon energization of one of the select magnets 40, the forward end of the armature extension 39 will be raised upwardly thus moving the associated select tape 32 through a short vertical distance.

Hold magnets 49 are also arranged in two rows and are staggered to permit armature extensions 48 to lie in plane. The magnetic circuit of each hold magnet is from the core through L-shaped pole-piecetl, pivoted armature 58 and return to the core. Armature extensions 48 are firmly affixed to their respective armatures 58 and are bifurcated at their frontmost ends to accept hold-tape threaded connectors 46. The positioning of the hold tapes 4| is accomplished through the adjustment of nuts 47. Hold tape length-of-travel is adjusted by means of studs 59 which bear against plate 6D and which may be locked in position by nuts 6|. Under energization of one of the hold magnets 49, the frontmost end of the armature extension 48 will be moved to the right thus moving the associated hold tape 4| through a short horizontal distance to the right. Springs 50 tensioned between bracket 62 and bracket 63 on armature extension 48 serve to return the holdtapes 4| to their unoperated positions upon deenergization of hold magnets 49.

The function of the contact rods 25 and the contacting media 3| thereon during operation of the select tape 32 and hold tape 4| will now be described in reference to Figs. 4 to 9, inclusive. In these figures, no attempt has been made to depict the contacting media. It is to be understood that the particular configuration of the apertures in the select and hold tapes is exemplary and may be modified within the scope of the invention.

Fig. 4 depicts the interrelationship of the elements at a typical cross-point at a time at which both select tape 32 and hold tape 4| are unoperated. Upon operation of the select magnet associated with the depicted select tape, each of the contact rods 25 associated with that particular select tape will be pivoted upwardly to assume a position as shown in Fig. 5. The contact rod has thereby been raised sufficiently so that it may be engaged by the hold lug 54 upon the subsequent movement of hold tape 4|.

Referring now to Fig. 6, with the select tape operated, energization of a hold magnet and the resulting operation of contact rod 25 at the selected cross-point to be engaged by hold lug E4 and moved to the right.

Since the lower edge of aperture 33 in select tapethe hold tape 4| will cause 2.: is cut at an: approximat ly 45;-d sr e an ler contact the contact rod will be rolled slightly so that, good, electrical contact is assured and also so that the wear on the contacting media ill will bedistributed over theirsurfaces. As, is; apparent in. Fig. 6, the contact rod is, moved sufficiently so that both the line; andtrunk conductors. are deflected. against the tension of their respective springs. 6 and I9.

Inorder to release the switch for further functioning in so far as possible, it is. desirable to be able to release the select tape and still maintain the previously selected contact closure. Such is possible in thepresent: invention as is exemplified in Fig. '7. Upon the deenergization of the select magnet and the consequent release of the select tape, the contact rod 25 is retained in a sta tionary position and in intimate contact with the line and trunk conductors by the downward force of the tensioned line conductor i by the force to the left exerted by the tensioned trunk conductor l3 and by the force at degrees upward. and to the right exerted by the hold lug 64.

Fig. 8 demonstrates. that the contact rods at non-selected cross-points are not aifected by operation of a hold tape. With the select tape 32 unoperated, actuation of hold tape ll will not affect the contact rod 25 since hold lug 5% will pass above the contact rod. If, then, while hold tape 4i remains operated. to hold a selected crosspoint, a subsequent switching operation causes select tape to be operated, as in Fig. 9, the contact rod 25 will be prevented from moving upwardly by its contact against the lower surface of hold lug M. This is desirable since the fact that the hold tape is operated indicates that line conductors i are already in circuit with a selected set of trunk conductors l3, and an additional trunk should not be connected into this circuit nor should a contact rod be permitted to strike the line conductor for such impact might disturb the quality of conduction in the selected circuit.

Referring now to Fig. l, provision is made for actuating a series of auxiliary contacts upon the operation of any of the select magnets to or hold magnets 49. Such supplementary contacts are useful in operating auxiliary circuits to indicate which sets of line conductors 4 or sets of trunk conductors [3 are being used, as indication of the extent of traflic over a switch or series of switches, or for any other such circuit function. It is contemplated that these auxiliary con-- tacts may also be employed to place a resistance in. series with the hold magnets upon the operation thereof in order to provide rapid initial oper- -i ation and still reduce the power consumption during the holding period.

The auxiliary contacts which are associated with each select magnet Bil comprise pair of spaced terminals mounted in a. slotted insulating block 555 at the top of the switch and locked in place by insulating block nibs El: The upper contact rod 25 in each vertical row thereof is provided with additional contacting media (38 which are. matable with the associated pair of spaced terminals 65 uponthe upward movement of the contact rod. It is apparent, therefore, that the operation of any select magnet 48 will cause auxiliary circuits to be closed through associated pair of terminals 65".

The auxiliary contacts which are associated; with each holdmagnet 49 may comprise a seriesof mating contact springs 65 and 1 0 molded in insulating blocks H. These insulating blocks H may be mounted between upper andlower guideplates. 12 and 13 which, in turn, may be supported by brackets 1.4 and I5. It has been found to be preferable to provide twin contact springs 69 in. they outer layer matable with single contact springs Til in the inner layer. Referring now to Fig, l and to the enlarged view of Fig. 3, certain of the contact springs 69 and 10 are restrained and. certain others are positioned and guided by stationary cards 16, of insulating ma,- terial, which are fixedly supported between guide plates E2, and 13. Others of the contact springsare actuated andguided by movable cards 11, of insulating material, which are slidably supported; between the guide plates 12 and 13 and which engage apertures therein. As may beseen in Fig. 1, upon the actuation of a hold magnet. 49 and, the consequent movement of the armature extension 48 to the right, adjustable bolt 18 will operate itsrespective movable card 11. Referring again to.Fig. 3, it will be noted that the inner single contact springs 1a are preformed so as to be pretensioned outwardly to engage notches. along the inner edge of the stationary cards 16, and to pass around the inner edges of extended portions, "is of movable cards H. The outer twin contact springs (39 pass through apertures in stationary cards Hi to engage apertures 80 in movable cards H. and are pretensioned inwardly. Whether the inner single contact springs 10 are fixed: rest against the stationary card 16 or whether they are movable and rest against the inner edge of movable card 11, and whether the outer twin contact springs 69 are fixed and rest against the edges. of the apertures in a stationary card 16 or whether they are movable and rest against the inner edges of the apertures 80 in a movable card l1 depends upon the configuration of those two cards, which is determined by whether it is desired that the contacts close or break auxiliary circuits upon energization of the. associated hold magnets so. In the embodiment. as depictedin Fig. 3, the contacts are arranged tobrealr. auxiliary circuits upon operation of the hold magnet, and, therefore, the configuration of thecards is such that the innersingle contact springs Hl are fixedly restrained by the lower edge of the stationary card 15. The outer twin contact springs 69, which are pretensioned in-. wardly so as tonormally be in contact with their mating contact springs '50, are normally out of contact with both of the operating cards; but upon operation of the movable card '51, the inner edges of the apertures 88 therein will force the twin contact springs 59 outwardly and cause the associated circuits to be broken.

The sets of line and trunk conductors which have been described as comprising four conductors per set may, in practice, have either more or fewer conductors as the circuit requirements may dictate. It is also contemplated that additional sets of conductors may be placed in the area behind thev actuating select and hold tapes, connection between such additional sets of conductors being accomplished by additional contacting media on the contact rods. It is evident that many possible embodiments may be made of the above-described invention, and that many changes may be made in the embodiment above set forth, and it is to be understood that all matter hereinbefore set forth, orshown in the ac- 7 companyingdrawings, is to be interpreted as illustrative and not in a limiting sense. What'is claimed is:

1. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a select tape associated with each set of trunk conductors and having a plurality of openings therein, one for each set of line conductors, a hold tape associated with each set of line conductors and having a plurality of openings therein, one for each set of trunk conductors, sets of contacting media each associated with one of the crossing points of said sets of line and trunk conductors and operable through the conjoint operation of one select tape and one hold tape, and means to move said tapes to effect electrical connection between said sets of line and trunk conductors.

2. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a select tape associated with each set of trunk conductors and having a plurality of openings therein, one for each set of line conductors, a hold tape associated with each set of line conductors and having a plurality of openings therein, one for each set of trunk conductors, a plurality of contact rods, one associated with each crossing point of said sets of line and trunk conductors, arranged to pass through the associated openings in said select and hold tapes, and operable through the conjoint operation of one select tape and one hold tape, and means to move said tapes to effect electrical connection between said sets of line and trunk conductors.

3. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a select tape associated with each set of trunk conductors and having a plurality of openings therein, one for each set of line conductors,'a hold tape associated with each set of line conductors and having a plurality of openings therein, one for each set of trunk conductors, a plurality of contact rods each having sets of contacting media associated therewith, each of said contact rods passing through the associated openings in said select and hold tapes at a crossing point of said sets of line and trunk conductors and operable through the conjoint operation of-one select tape and one hold tape, and means to move said tapes to cause said contactin media to effect electrical connection between said sets of line and trunk conductors.

4. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a select tape associated with each set of trunk conductors and having a plurality of openings therein, one for each set of line conductors, a hold tape associated with each set of line conductors and having an opening therein for each set of trunk conductors, each of the openings in said hold tape being so shaped as to forma depending lug, a plurality of contact rods having sets of contacting media thereon, one of said contact rods being associated with each crossing point of said sets of line and trunk conductors and passing through the associated openings in said select and hold tapes, means to move a selected one of said tapes to move a selected one of said contact rods, and means to move a selected one of said hold tapes to cause the depending lug thereof to further move the selected 8* one of said contact rods toeffect an electrical connection between the selected associated sets of line and trunk conductors.

5. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a select tape associated with each set of trunk conductors and having a plurality of openings therein, one for each set of line conductors, a hold tape associated with each set of line conductors and having a plurality of openings therein, one for each set of trunk conductors, a plurality of contact rods each having set of contacting media associated therewith, each of said contact rods passing through the associated openings in aid select and hold tapes at a crossing point of said sets of line and trunk conductors, and operable through the conjoint operation of one hold tape and one select tape, means to move said tapes to effect electrical connections between said sets of line and trunk conductors, pairs of spaced terminals mounted adjacent certain of said contact rods, and additional contacting media on said certain contact rods engageable with said spaced terminals upon operation of said certain contact rods to establish auxiliary electrical circuits.

6. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a select tape associated with each set of trunk conductors and having a plurality of openings therein, one for each set of line conductors, a hold tape associated with each set of line conductors and having a plurality of openings therein, one for each set of trunk conductors, sets of contacting media each associated with one of the crossing points of said sets of line and trunk conductors and operable through the conjoint operation of one select tape and one hold tape, means to move said tapes to effect electrical connection between said sets of line and trunk conductors, and further means associated with and operable by said last-mentioned means to control auxiliary electrical circuits.

'7. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a contact rod at each crossing point of said sets of line and trunk conductors, a select tape associated with each set of trunk conductors and having an opening therein for each associated contact rod, an edge of each of said openings serving as a camming surface for its associated contact rod, a hold tape associated with each set of line conductors and having an opening therein for each associated contact rod, each of the openings in said hold tape so shaped as to form a depending lug one edge of which serves as a camming surface for said contact rod, means to move a selected one of said select tapes to move a selected one of said contact rods, and means to move a selected one of said hold tapes to cause the depending lug thereof to further move the selected one of said contact rods to efiect an electrical connection between the selected associated sets of line and trunk conductors.

8. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a contact rod at each crossing point of said sets of line and trunk conductors, a select tape associated with each set of trunk conductors and having an opening therein for each associated contact rod, one edge of said opening being at an angle with the direction of movement of said select tape and serving as a camming surface for said contact rod, a hold tape associated with each set of line conductors and having an opening therein for each associated contact rod, each of the openings in said hold tape so shaped as to form a depending lug the sides of which extend at an angle to the direction of movement of said hold magnet and serve as camming surfaces for said contact rod, means to move a selected one of said select tapes to move a selected one of said contact rods to a position wherein it may be engaged by the associated depending lug, and means to move a selected one of said hold tapes to cause the camming surfaces of said select tape and of said hold tape depending lug to force the selected one of said contact rods into rolling contact with the selected associated sets of line and trunk conductors to effect an electrical connection therebetween.

9. In an automatic telephone switch, sets of line conductors and sets of trunk conductors arranged coordinately but out of contact one with the other, a contact rod at each crossing point of said sets of line and tape associated with each set of trunk conductors and having an opening therein for each associated contact rod, an edge of said opening serving as a camming surface for said contact rod, a hold tape associated with each set of line contrunl; conductors, a select ductors and having an opening therein for each associated contact rod, each of the openings in said hold tape so shaped as to form a depending lug the opposite edges of which serve as camming surfaces for said contact rod, means to move a selected one of said select tapes to move a selected one of said contact rods, and means to move a selected one of said hold tapes to cause the depending lug thereof to further move the selected one of said contact rods to effect an electrical connection between the selected associated sets of line and trunk conductors, further engagement of other contact rods with said selected line and trunk conductors being prevented upon the subsequent operation of a select tape by the hold tape depending lug.

CLARENCE N. HICKMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,506,271 Reynolds Aug. 26, 1924 1,523,411 Forsberg Jan. 20, 1925 1,553,313 Goff Sept. 15, 1925 1,647,792 Gent Nov. 1, 1927 2,339,472 Frederick Jan. 18, 1944 2,357,108 Hartley Aug. 29, 1944 2,358,095 Parker Sept. 12, 19 A 

